The purpose of this study is to evaluate the response to pomalidomide and dexamethasone in relapse and refractory MM patients who are progressive and did not achieve at least a partial response to bortezomib and lenalidomide. This study will determine the efficacy and toxicity profile of 2 modalities of pomalidomide in patients with advanced myeloma, previously heavily treated characterized with adverse prognostic and that are in desperate need of novel therapeutics.